1. Field of the Invention
The present invention relates to an information management apparatus and an information management system, which manage information collected in a plant, a factory, or the like.
Priority is claimed on Japanese Patent Application No. 2011-037259, filed Feb. 23, 2011, the contents of which are incorporated herein by reference.
2. Description of the Related Art
All patents, patent applications, patent publications, scientific articles, and the like, which will hereinafter be cited or identified in the present application, will hereby be incorporated by reference in their entirety in order to describe more fully the state of the art to which the present invention pertains.
In the related art, a distributed control system (DCS) in which field devices (a measurement unit and an operation unit) are connected to a device management apparatus for managing and controlling the field devices via a communication bus has been constructed to implement an advanced automatic operation in a plant or the like. In the DCS, a plant information management system (PIMS) is usually introduced to accumulate collected data over a long period and provide the accumulated data in a necessary format at a necessary time so as to easily manage an enormous amount of data (for example, process data) collected in the plant or the like.
By introducing the plant information management system, operation situations in the plant or the like can be managed in real time and also management of production results based on ledger sheets, simplified analysis based on trend graphs, and advanced processing based on prediction/diagnosis/multivariate analysis can be performed. In Japanese Unexamined Patent Application, First Publication No. 2007-58559, a plant monitoring system, which has a plant information management apparatus for collecting and managing process data of field devices and monitors a plant using the process data managed by the plant information management apparatus, is disclosed.
Incidentally, it is significantly important to collect measurement values correctly measured by field devices so as to accurately perform the management of the production results based on the ledger sheets and the simplified analysis based on the trend graphs described above by introducing the plant information management system. In particular, because a process of extracting a difference between measurement values measured in time series and observing a change is usually performed in the above-described advanced processing, the validity of each measured measurement value is significantly important.
Here, the plant information management system of the related art collects only measurement values from the field devices without collecting information indicating statuses of the field devices or statuses of paths from the field devices to the plant information management system. Thus, there is a problem in the validity of a measurement value, for example, because collected information is also handled as a normal value in the plant information management system when the field device fails or when a device (for example, a router) located on the path from the field device to the plant information management system fails.
In addition, if a measurement value of which the validity is doubtful has been collected, it is necessary to specify its cause and exchange the device. However, in the related art, it is time consuming to specify the cause because the statuses of all devices located on the path in which a measurement value has been collected should be checked when the measurement value of which the validity is doubtful has been collected because the information indicating the status of the field device or the status of the path from the field device to the plant information management system is not collected in the plant information management system as described above.